


Bloody Paradise

by orphan_account



Category: Underfell - Fandom, Undertale, underswap
Genre: Alternate Universe, Dimensions, M/M, Maybe some mention of gore here and there, Portals, Underfell, selfcest, some illustrations, underswap - Freeform
Language: English
Status: In-Progress
Published: 2016-03-12
Updated: 2016-04-13
Packaged: 2018-05-26 00:59:52
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 5
Words: 3,575
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6217279
Author URL: https://archiveofourown.org/users/orphan_account/pseuds/orphan_account
Summary: <blockquote class="userstuff">
              <p>A trail of suspicious red snow and curiosity causes Blue's life to be turned to hell.<br/>Red is drawn to something about Blue and takes him in, interested in his alternate self. </p><p>"It's kill or be killed here, buddy. Survival of the fittest."</p>
            </blockquote>





	1. Prologue

Hurried footsteps sound behind Sans, on his lookout for humans. He freezes, slowly looking behind him.

"Hello? Anyone there?" He asks, turning his body and looking around cautiously. He moves to locate the source as best he can, noticing a trail of faded red, quickly being dusted by snow. The fresh snow crunches beneath the skeleton's feet as he takes a few steps and follows the trail with his eyes.

Deciding it was a good idea to follow the mysterious red before it's covered completely under a blanket of white, he runs. Sans runs through bushes, around trees, into rocks (ouch), until he comes upon a red portal. Upon sight, the "portal" that was showing red, now shows a land, similar to Snowdin, but covered in what looks like dust. 

Sans gulps, picking up a pebble and throwing it in. It makes it through without any trouble and slowly but steadily, he puts a foot through. No pain. Stepping through, the short skeleton finds himself in a universe where the sky is red, the land is a mix of dust and snow, and the wind howls fiercely. Sans, being too busy being shocked by his new surroundings, did not notice the sound of crunching snow behind him.

"What the fuck are you doin' here?" Sans lets out a startled cry, turning around too quickly and falling on his bottom. He looks up to see who the voice belongs to and is met with a red skeleton. With the black jacket, fur, and golden tooth, the scarier-looking Sans can convince anybody that he's part of a threatening gang that won't hesitate to beat you up. He probably is, though.

"I-uh... Uh..." Sans's mouth opens and closes, trying to find words.  _Portal! Porrr...tal. Portal. Portal?_ Sans frowns, nearly zoning out trying to figure out what to say. He stands up, clearing his throat and tries to look into the burning red eyes. "A red portal! I found it while following a trail of red. The red Sans scowls, shaking his head. 

"Fuck, I thought I closed the portal!" Sans says in his gruff voice. Swap Sans flinches at his colorful language, adjusting his scarf. The mix of dust and snow makes Sans want to throw up but he swallows the magic, frowning ever so slightly.

"If I may ask, alternate me, why is there... Erm, dust everywhere?" Narrowing his eyes, the blue Sans tries to focus on anything but the thug in front. 

"What? You can't be serious. These are the dust of monsters, y'know, when they die. Heh, it's their fault for getting in my way." Red Sans dusts off his jacket, walking a few steps before turning back to the blue one. "Oh, and the red? It was ketchup. Personally, I prefer mustard, but ketchup was the only thing available from that universe. Whatever, it's tolerable." 

"Wait!" The new skeleton, about to go off in his own direction, is stopped by the other. "What... Happened to the portal?" He points behind him with his thumb. He was so dazed by the red sky, suspicious dust and red Sans that he didn't realize the portal's disappearance.

"Oh, that?" Sans thought for a moment before chuckling. "You're stuck here, buddy. At least, not for eternity. I don't know how to control portals, they usually just come randomly. And unfortunately, you're stuck in this hellhole temporarily until it opens back up. And here's a tip, bud. It's either kill or be killed, here."

"Kill or be killed? What does that mean? You don't mean that..." Slowly, the trapped Sans slides onto his knees, looking at the ground in shock. 

"You know exactly what I mean." Chuckles Sans, beginning to walk away. When he notices the lack of footsteps, he turns around to see his more innocent self still staring at the ground, lost in thought. 

"Hey. C'mon, kid, you can't be serious. You've never killed before, have you?" Red didn't get an answer. Sighing, he crumbles. "You know what? Blue me, just stick with me for now. I'll teach you our ways some day, but it seems like you need to adjust to this place first. Don't take it the wrong way, I'm not helpin' you. Consider it pity." Walking over and giving the still in shocked Sans a hand, he jabs a thumb behind him.

"My house is that way. Don't know if yours is in Snowdin too, every universe is different after all." Blue didn't talk. He didn't talk much during the walk, either. 


	2. Chapter 1

It's been a few days since they met, and the two decided on calling each other "Red" and "Blue" to avoid confusion. Red told Blue not to go outside without him, or maybe don't go out at all. Blue made Red tacos for the first time after telling Red what he needed, and even though Red tells him that it doesn't taste that good, he devours it whole and asks for more.

"You know, Red, I've never seen you as a cuddler!" Blue jokes, gloved skeletal hands on his hips and a smile glued onto his face in a teasing way. Red snorts, looking away. Red lives with his own Papyrus and they only had two room. Giving Blue Papyrus's room would result in instant death, and neither of them wanted that. Red, maybe, though. So the two shared a room. And a bed. In the middle of the night, Red would randomly cuddle with Blue, which startled him the first time.

"Shut it, Blue. It's not funny." Red growls, face going a light red. 

"It's cute!" Argued Blue, smiling at him. 

"It's not! I'm not cute. I'm fierce, and I should be feared!" Salty Sans retorts, crossing his arms and huffing. On the way to the kitchen, the front door is thrown open and standing outside is Papyrus. 

"Sans!" Red and Blue both froze, looking at each other from afar. Blue was a deer in headlights; nothing to shield him from disaster. Shit's going down, and it ain't gonna be pretty.

"Uh, yeah, bro- I mean, boss?" Red looks over at his brother from the entrance of the kitchen, sweating nervously. He cursed to himself, mumbling on how he should have started training Blue sooner to be more useful in their universe than a useless heap of disgusting rainbows and sunshine. 

"Did you find-" Papyrus slams the door shut and was about to approach the other when he notices the other Sans. And Blue,  _stupid_ Blue, decides to speak to him. 

"Hello, Red's Papyrus! I am Sans from another universe!" He greets. Papyrus snorts, shaking his head.

"You seem quite merciful here... 'Sans.' We'll have to change that." He chuckles darkly, walking over and grabbing Blue by the scarf, dragging him into the evil Papyrus's room. "Sans, stay there. Once I'm done with him... You'll have the responsibility to train him further." Blue gulps, taking in all the light before the darkness engulfs him. "Now, I'll be right back. I need to get a useless monster to start your training." 

Papyrus leaves Sans in the room, locking the door. He has a terrible feeling and even began to shake, predicting what's going to happen. 

"Red," Blue whimpers, crawling over to the door and knocking. "Please let me out! I'm scared." No answer. He sucks in air and lets out a deep sigh. Crawling over to a corner, he pulls up his knees to his chest. "Don't be scared, Sans. The great Sans can never be defeated!" Fake reassurance. 

In the distance is the front door opening, and after a minute, the room door. Papyrus-  _no_ , Blue thought.  _He's not like my Papyrus. He doesn't deserve his name!_ Blue decides on calling the bad Papyrus Evilrus, because that's what he is. Evil. Evilrus had a bag with him, a moving one as if a monster was in it.

Boy, was he right.

"You are required to kill this monster." Evilrus says, straight to the point. He tosses the Snowdrake out of the bag, stepping on the struggling monster without mercy. Snowdrake's eyes were red enough to brighten the room, even if it was just a bit. 

Sans shakes is head in refusal, pressing himself against the wall, beginning to shake even more.

"Useless piece of shit. If you don't kill this monster here and now, you're the monster going to get killed." Sharp and direct. Sans couldn't handle it. His life, or Snowdrake's? He had a big heart, he couldn't kill even if he wanted to! Although, as far as Blue knows, he's the only monster in this universe to care about anyone. He has to be the first to show this world how to be nice. And Snowdrake..? He seems like a jerk, spitting insults at Evilrus and trying to inflict damage on him.

His life or Snowdrake's? The question is replaying constantly in Blue's head, and he couldn't handle it. He has to live. He has a goal. Snowdrake's going to die either way, he knows. He wants to end its misery in this hellhole.  _Forgive me, Snowdrake!_ He thinks, summoning a bone with his magic. Wiping tears away, he stands up and approaches it.

For the first time in his entire life, he regrets a decision.

**Notes for the Chapter:**

> I'm sorry, Blueberry darling. ♥♥  
> I will try to make chapters longer, I promise!


	3. Chapter 2

**Notes for the Chapter:**

> Fuck, if I accidentally write in second person, it's my bad. =')

Papyrus left to go out again. He won't be back for at least another few days, and he expects Blue to be more trained and tougher when he gets back. Red knows this for a fact. 

He hears Blue's cries in the room. He knows what he just did. And he feel kind of bad for trapping an innocent soul, even if Red wouldn't admit it. He doesn't understand why Blue just doesn't listen and move on with life; it's either kill or be killed. 

No longer will he just sit there and hear the other's cry, someone who he's been getting to know so well for the past few days... His kindness to Red, unlike others who treat him cruelly like how he treats them, makes his heart ache just to think how much he's done for him and how little he's done for him. So he climbs the stairs to his brother's bedroom, grabs his room key because the keys are the same for both room, and unlocks the door.

Dust. Blue's covered in dust, the floor's covered in dust, dust is everywhere. Tears made of magic. It mixes with the dust. And Red just feels, just a  _tiny_ bit of sympathy for him. He was raised in a softer world. But Red wasn't. He's used to it. Blue isn't. Does his brother give a shit? No. Does Red? With the tiniest percentage. 

"Blue." Red walks over to the figure, sitting down. He was surprised when Blue leaped onto him, hugging him tightly and crying into his chest. Red wrapped his arms around Blue, relaxing to the touch and staring ahead blankly. 

 

After quite a while, Red stood up and picked up a sniffling Blue, carrying him to their room and laying him down on the bed. Red lays down next to him, facing Blue. He sniffles, Red wiping tears away from Blue's eye sockets and pulling him closer.

"Listen, kid. This is the only act of mercy I'll give you right now, alright? Don't expect this from me another time." Blue nods his head, cuddling into Red and yawns. Red yawns also, fiddling with Blue's scarf before drifting into sleep as well.

 

Red would have had a good, long sleep, if it wasn't for poking at his face. Grumbling, he pushes the hand away without opening his eyes. The hand continues and he has to hold it down in a tight grip for it to stop, slowly going back to sleep.

"GOOD MORNING, RED!" Holy shit, if it wasn't Blue, he'd kill him by now. Growling, he tries to cover his ea-- never mind, scratch that, he has no ears. It's fine, he's dead inside anyways.

"Shut up, Blue! I'm trying to sleep!" Red smashed his skull into a pillow. The warm sheets were pulled off of him and he dies a little more on the inside, somehow. A warm body is wrapped around him though, and it's forgiven that the sheets are gone.

"Wake up, Red. You can't be sitting here all lazy, now, can you?" Red groans, wrapping his arms around the other's torso and opened his eyes. Blue was sitting on top of him, stars in his eyes and it's like yesterday never happened.

"Eh, it's debatable." The tired Sans sits up, rubbing his eye sockets before falling against the soft-hearted Sans. "God, am I exhausted. And holy shit, are you warm for a skeleton." Red cuddled against Blue, sighing. Oh shit, that's right.

Training.

Pinning the blue skeleton on the bed, he looks at the other. It could be mistaken greatly as an intimate moment, but it wasn't. Suck it, shippers. 

"Ey Blue. Hate to break it to ya', pal. But uh, training. You're going to have to start doing some training." It got silent after he said that, and Blue looks away, his bright smile fading. "But hey." Red rests hid palm against Blue's cheek, making him look at him. "I'll go easy on you temporarily, a'ight?" Blue nods, narrowing his eyes.

"But I don't want to kill." He whispers. Red presses their foreheads together, sighing.

"Kid, you have to. Promise, you'll get used to it." The moment was one to treasure, with the two closing their eyes and leaning in. A sudden jerk of movement, Red moves away and gets up. "Understand?"

"I'll try..." Blue's face was covered in slight blue as he leaves the room to presumably make tacos for breakfast. Red collapses onto his bed, covering his face with his hands and cursing a variety of words at himself.

"Holy shit, Red. What the fuck were you thinking, you son of a bitch." Red sulked in his words for quite a bit before leaving and entering the living room, collapsing on the couch and hogging it while turning on the T.V. Another episode of MTT, great. That show fucking sucks, only Papyrus watches that shit, because the sick fuck is hella obsessed with the star of the show. What's his name? Pestatton? Doesn't matter.

He does know what matters, though. The tacos that Blue brings into the living room. Delicious, he'll eat them all at once. 

**Notes for the Chapter:**

> I lied, I can't write longer chapters. I'm too busy bathing in cliff hangers.


	4. Chapter 3

**Notes for the Chapter:**

> Ohhhh shit, guys! I'm sorry I didn't update sooner, unfortunately, a new ship and fandom has taken me in.   
> Don't worry, though, FellSwap Sanses is fucking bomb as hell, still.
> 
> This chapter is rather short, I apologize! I whipped one up quickly just because I didn't want you guys to die from the lack of chapters.  
> Then again, you guys will die over the shortness of this chapter. Lose, lose, either way, I suppose!

So many days. So many days have went by and it seemed like Red was drifting away. Distancing, growing more colder. Red. The color of human blood, is what Blue found out. Dust covered his clothing every time training was finished, and he believes that his magic can no longer produce tears after all the training. 

He learns that Red does not want to be called Red no longer. He wants to be Sans again. He says Red and Blue is a dumb nickname, he insults him every day now. It hurts, Red-  _Sans_ was treating him as if he has lived here his whole life. Like he wasn't a fragile butterfly, which he supposes he kind of isn't now.

But something bad happens. Both Sanses were sitting in silence a good distance away from each other, when Papyrus had suddenly swung the door open, inhaling sharply before collapsing and just before he hit the ground, he turned to dust. 

And it horrified him.

Someone as strong as Papyrus/Evilrus was killed, and it was a mystery as to how the heck it happened. Has he been dragging himself to the house with an injury so bad? Reckless of him. Blue Sans was honestly kind of hurt, he was getting to know Papyrus better and his kindness started to get to him. It was like he was finally starting to open up with him, accept him as his brother. Accept Fell Sans as his brother.

He can't, now. Not as a pile of dust.

And both Sanses looked at each other, horrified, eye sockets wide. 

"O-Oh my god, they killed Papyrus!" Squeaked anti-swear Sans.

"You bastards!" Growled all-out-swearing Sans, shaking a fist in the air.

Laughter, evil laughter. And who came into the house was who blue Sans didn't recognize... Undyne. The sweet nerd who loved these silly cartoons called 'Anime' was not this scary, heavily armored, fish. And boy, was she practically bathing in dust.

"Oh, Papyrus. You didn't listen to me. And look what happened now, I'm standing in your dust. What a shame, what a shame. You left these absolute  _weaklings_ here defenseless because of your hilarious choice to disobey me,  _leader_ of the royal army. And now, I get to have a fun... Fun...  _Fun_ dust party!" Chaotic laughter fills the room, as she picked up Swap by his scarf. "And the party will start first with your dust,  _punk_."

Sans was scared to the bone, and it wasn't a pun. If possible, beyond scared, even. And she strikes her target, only something else was hit.  _Someone_ else. And it was someone he cares for a lot. And it hurt to see him slowly fade away into dust. And it was painful. Painful. Somebody who has finally returned after so long, someone who he recognizes as anything but a killer.

Red.

**Notes for the Chapter:**

> I kind of feel bad for putting in a reference to my new found home (Undertale's still my second home, worry not, friends!) in this chapter. It should be easy to find, though, honestly! It was really tempting. Sorry for the shortness, once again!
> 
> Also, this is why I felt bad for you. <3


	5. Chapter 4

**Summary for the Chapter:**

> It's been like a month, or something. I feel so guilty about not updating for a while!  
> So here, angst.  
> A nice welcome back gift.  
> (;
> 
> (Also a celebration for my other fandom, Homestuck! It ended today and now I'm upset. Hence, angst!)
> 
> And because I'm pretty much out and done with the Undertale fandom, this is a wrap up before the final chapter! 
> 
> Which probably won't be out for at least another month and a half, knowing me.

That's when he broke. Blue realized that the moment he stepped into this new universe, he was fractured. Almost breaking, but held together by the thinnest string. Maybe, but Blue isn't sure, Red is that string.  _Was_ that string.

And seeing Red die in front of his eyes probably proves that idea. He can mentally feel a string  _snap_ , and before he knew it, he summoned a bone, swung, and impaled Undyne with it. 

Tears spilled out of his eyes, and he brushes a finger and tries to suck up the tears. His attempts failed, though, as he runs back over to where Red lays (surprisingly not as a pile of dust). 

"Red, are you okay?" He cries out, hoping,  _just hoping_ that Red would respond. His soul twisting and aching, he holds the other Sans close to him. 

"N-No," Blue lights up at that, but realizing that Red isn't okay and is still in fact, dying, more tears spilled out. "L-Listen, Blue. I love you, alright? So you're me. Whatever. But I have something to confess to you before I-" he lets out a cough, "- turn into a heap of useless dust." 

"What? Red, please don't go!" Red shook his head, smiling, faint red tears showing in the corner of both his eye sockets.

"You could have gone home this whole time. I have the ability to control the portal." His raspy voice said, huddling close to Blue and praying he won't be angry. "But I was being selfish, lied to you, just so you would be able to stay with me. You interested me, Blue." He closes his eyes, letting it sink in.

"I don't care, because if it wasn't for that, I wouldn't have met you!" Blue cried out, shaking his head violently. "Please, please, please, just try to hang on! I'll help, I'll try to help!" Red laughs at that, opening an eye to look at his beautiful self.

"It's time for you to go home, Blue. I wish we could have been something more." He lets out a pained, raspy laugh, slowly turning into dust from the bottom up, a red portal opening up. "And hurry your ass up, the portal ain't gonna last forever, buddy."

Monster dust was the only thing in Blueberry's arms, now, and practically all of it was already falling to the floor. He disappears into the room, reappearing in a matter of seconds with a dustpan and broom. Sweeping the dust into the pan (careful not to mix the dust into each other), he pours Papyrus's dust into container, Undyne's into a fish tank (he never knew Red and Papyrus had pet fish!), and Red's, he took off his scarf and carefully poured his dust into the bandanna and tied it. He noticed the portal fading, and quickly grabs each of the items with magic (except for his scarf, he held that close to his chest), and ran through it.

He appeared on the other side of the portal. It was his actual house, now. Papyrus must be in his room, doing whatever the hell he does, while Blue hums a sad tune, placing each of the objects side to side by each other on a table in his room.

* * *

It's been a few days since his return, his brother Papyrus giving him a big hug when he finds out he was never really lost in the first place.

Blue requested a strange request according to Papyrus, to call him, "Blue." He obliges anyway. And it's been wild since his return, and in present day, he was frightened when the dust were gone. Happiness returned at full force when he instead, finds 3, very tiny, skeleton brothers and a small fish child in the kitchen. The three of them represented Red, Papyrus, and Undyne, and Blue was more than happy to give the smaller Undyne to the royal scientist Undyne as a little helper and company, and Blue gave the Papyrus to, well, Papyrus, and kept Sans to himself.

The Sans, after all, did remind him greatly of Red.

Hell, he even called him Blue, without Blue telling him his name.

And he knew that his name, was Red.

 

**Notes for the Chapter:**

> Editing? No way!
> 
> I actually rushed this chapter out because I had to go to bed while writing this, and I didn't want to forget about the idea so I just kind of.  
> Did it without editing?
> 
> Apologies for any mistakes!


End file.
